How to override/change the default theme in the source?

Is there a list/guide somewhere of all the hooks in the source that relate to changing/overriding the default Xfce desktop theme? Over at Devuan we're having trouble sorting this so that we can rebuild the appropriate packages. Searches have plenty of guides for changing the theme in an already installed desktop not the source. Any suggestions/pointers would be appreciated. Thanks.

Re: How to override/change the default theme in the source?

xfce4-settings (xfsettingsd) is the Xfce component that applies gtk settings. I am unaware of a list or guide that goes into any detail, so you're probably stuck with trawling through the code.

Can you give an example of what you're trying to do?

We're trying to integrate the custom wallpaper, WM theme (including xfwm), cursor and panel settings. We already have an idea of where the changes need to be made but I'm not actually them or the packaging so can't provide details. All I know is that the first attempt broke some things in the main settings menu. I was hoping there was a list of specific hooks and their location. Or maybe even a shell script to do everything all at once. In any case, I'll share the links . . . there might be some useful info in there. And I'll poke around them - maybe something will pop out at me. Thanks.